F rom its hiding place under his mattress, Merrin pulled out a slim, dog-eared, leather-covered book with the title The Darke Index just visible in faded black letters. He grinned. At last he could read this without having to hide it from nosy-parker Simon Heap and the annoying Lucy. She was even worse than Simon and spent most of her time saying things like: "What are you doing, Merrin?" and "What's that you're reading, Merrin? Show me. Oh, go on, don't be so sulky, Merrin."

Ever since Merrin had found the book at the back of a dusty cupboard that Simon had made him clean out, he had been fascinated by it. The Darke Index spoke to Merrin in his own language. He understood the spells, the rules - and he particularly liked the section that told him how to break the rules. Here was a book written by someone Merrin could understand.

At night, in his small cell, curtained off from the Observatory (because Jenna had once turned the door into chocolate), he would take a tube of Glo Grubs and read for hours under his covers. Simon had noticed the light and teased him about being afraid of the dark, but for once Merrin did not rise to the provocation. It suited him that Simon asked no more questions about the light that glowed on into the early hours of the morning. If Simon wanted to think that, let him. One day Simon Heap would find out that Merrin was most definitely not afraid of the dark - or, more to the point - the Darke.

Now, Merrin lit all the candles he could find - Simon was stingy with candles and only allowed one to be lit at a time - and he placed them all around the huge, circular chamber of the Observatory. The twilight he had caused by pulling down the blinds was replaced by the warm glow of candlelight.

Merrin told himself that he was doing this because he needed the light to read, but Simon had also been a little bit right: Merrin did not like the dark - particularly when he was on his own.

Merrin decided to enjoy himself. He raided the tiny kitchen for the last of Lucy's pies - he found two steak and kidney, one chicken and mushroom and a squashed apple dumpling - then he poured himself a huge mug of Simon's cider. He put it all on the tiny table beside his narrow, lumpy bed and added a few musty chunks of the chocolate door that he had found in a dusty corner under the bed to his pile of food. Then he went and took the thick woolen blanket that Simon kept on his bed. Merrin hated being cold but he usually was, since the Observatory, being cut deep into the slate cliffs, always had a deep chill.

Looking forward to a whole day of doing exactly what he wanted, Merrin wrapped himself up in the blanket and, not even bothering to take his shoes off, he got into bed and started on his stash of food.

By midmorning Merrin's book had fallen to the floor. He was fast asleep amid a sea of pastry crumbs, furry lumps of chocolate and discarded bits of kidney, because ever since Simon had told him what kidneys actually did, they had made Merrin feel sick.

One by one, the candles in the Observatory burned down but Merrin slept on until the dying splutters of the last candle jolted him awake. He woke in a panic. Night had fallen; it was pitch-dark and he couldn't remember where he was. He jumped out of bed and collided with the doorpost. As he reeled back, Merrin saw the white dish of the Camera Obscura illuminated by a thin shaft of moonlight that had found its way through a gap in the blinds. Panic subsiding, he took out his tinderbox and began lighting new candles. Soon the Observatory glowed with warm candlelight and felt almost cozy - but what Merrin had planned was about as far removed from cozy as it was possible to get.

Merrin picked The Darke Index off the floor and opened it to the last page, the title of which was: Darkening the Destiny of AnOther

or The Ruination of Thine Enemy by Use of the

Two-Faced Ring

A Tried and Tested Formula Used with Great

Success by the Author

Merrin knew that part by heart, but he had read no further because of the next line, which said: Read no Further until thou art Ready to Do,

Else shall be the worse for You

Merrin gulped. Now he was Ready to Do. His mouth felt dry and he licked his lips. They tasted of old pie - not nice. Merrin fetched a glass of water, gulped it down and wondered whether it might be better to put the whole thing off until the next night. But the thought of another bleak day in the Observatory on his own, plus the possibility that Simon and Lucy might return at any time, was not good. He had to do this now. And so, with a scared feeling in the pit of his stomach, Merrin read on: First You Summon your Servant Thing

Merrin's heart thumped; this was scary. Summoning a Thing was something that even Simon had not dared to do. But now that he had started, Merrin dared not stop. Warily, as if he were pulling a particularly vicious spider out of its lair, Merrin drew the Summoning Charm from its pocket at the bottom of the page. The Charm - a wafer-thin black diamond - felt as cold as ice. As instructed, Merrin held the diamond against his heart and, with the cold of the stone boring deep into his chest, he recited the Summons. Nothing happened. No gust of wind, no disturbance in the air, no fleeting shadows - nothing. The candles burned steadily on and the Observatory felt as empty as ever. Merrin tried again. Nothing.

A horrible feeling crept up on Merrin - it was true, he really was stupid. Once again he read the words, saying them slowly. Yet again nothing happened. Over and over Merrin repeated the words, convinced that he must be missing something obvious - something that anyone else with half a brain would have immediately noticed. But no Thing appeared, no Thing at all. Getting angry now, Merrin shouted the Summons - nothing. Then he whispered it, he pleaded, cajoled - and in desperation he yelled it out backward, all to no avail. Exhausted, Merrin sank to the floor in despair. He had tried everything he could think of, and he had failed - as usual.

What Merrin did not realize was that his Summons - every single one - had worked. The Observatory was now actually seething with Things. The problem was he could not see them.

Things were generally not possible to see, which was fortunate, as they were not a pleasant sight.

Most Things were some kind of human figure, although not obviously male or female. They were usually tall, thin to the point of being skeletal and extremely decrepit, their clothes no more than a collection of dark rags. They wore miserable, sometimes desperate expressions mixed with underlying malevolence that left sensitive people who were unfortunate enough to meet their gaze feeling desperate for weeks afterward. Merrin - although he did not know it - had an aunt Edna who fit that description pretty exactly, but even he would have been able to tell the difference between his aunt Edna and a Thing - because a Thing looked dead.

It was then that Merrin read the second part of the instructions: Now Address the Thing,

Demand to See.

Remove its Invisibility.

"Aaargh!" yelled Merrin, suddenly realizing to his horror what had happened. Angrily, he hurled the book at the wall. How was he supposed to know the Things were invisible? Why hadn't the book said so before?

Half an hour later, Merrin had calmed down. Knowing that he had no choice but to continue, he picked up the book, found the crumpled page and began to follow the instructions. He recited the See, closed his eyes and counted to thirteen. Then, with a feeling of dread, he opened his eyes - and screamed.

Merrin was surrounded by Things. Twenty-six aggrieved, nose-out-of-joint, why-didn't-he-just-choose-me-aren't-I-good-enough-for-him Things were staring at him, their lips moving, mumbling and moaning but making no sound. They towered above him and stared at him so intently that even Merrin, who was not known for his sensitivity, felt a deep gloom rising inside him.

It was, he thought, all going horribly wrong. Simon was right; everyone was right; he was stupid. But now he was stuck. He had to continue or else it would, as the book had said, be the worse for him.

With a nasty feeling in the pit of his stomach, Merrin read the next instruction: Now Take with you your Servant Thing

To Find and Fetch the Two-Faced Ring

Merrin's heart sank when he read the words: the Two-Faced Ring. He still had nightmares about it.

A few months ago Simon had been grumpily cleaning up the Observatory, complaining loudly about Merrin's untidiness. Merrin, meanwhile, had hidden in the larder. He had been surreptitiously eating his way through a secret stash of cold sausages when he had heard Simon scream. Merrin had very nearly choked - Simon usually did not scream. Gasping and coughing, he had staggered out to see a truly terrible sight: a foul collection of rubbery-looking bones glistening with black slime was slowly stalking Simon across the Observatory. Clutching his garbage sack to him as though it were some kind of shield Simon was backing away with a look of utter terror on his face.

Merrin knew at once to whom the bones belonged - his old master, DomDaniel. It was the ring that gave it away. The thick gold and jade Two-Faced Ring that DomDaniel had always worn on his thumb shone out against the black sheen of the bones. "This ring," DomDaniel had once told Merrin,

"is indestructible. He who wears it is indestructible. I wear it, therefore I am indestructible.

Remember that, boy!" He had laughed and waggled his fat pink thumb in Merrin's face.

Merrin had watched the bones corner the terrified Simon. He had listened while, from somewhere deep within the bones, came a Darke hollow chant of destruction aimed directly at Simon. It had made Merrin want to curl up into a little ball, though he didn't know why. Luckily for him, he did not remember the time in the Marram Marshes when DomDaniel had directed the very same chant at him.

As the chant had progressed relentlessly toward its end - when Simon would be Consumed - Merrin saw Simon Heap change. But not in the way DomDaniel had planned. The fear in Simon's eyes was suddenly replaced by a wild anger. Merrin had seen that look before and he knew it meant trouble.

It did.

In one swift action - like a butterfly hunter after a prize specimen - Simon had brought his garbage sack down over the bones, yelling a Darke imprecation of his own. The bones had collapsed and some escaped across the floor, but the chant did not stop. Panicking now, Simon had scrabbled for the stray bones, throwing them into the sack just as he had been throwing the garbage a few minutes earlier.

Muffled by the sack, still the Darke chant had continued.

Frantically, Simon had hurled the last bone into the sack. Then, as if his life depended on it - which it did - he had raced across the Observatory, pulled open the door to the Endless Cupboard, hurled the sack inside and slammed and Barred the door. Then, to Merrin's amusement, Simon's legs had given way beneath him and he had collapsed onto the floor like a wet rag. Merrin had taken advantage of the moment to finish off the sausages.

But now Merrin was going to have to see those awful bones once more. And, worse, take the ring from them. But even worse, he was going to have to go into the Endless Cupboard to find them, which really scared him. The Endless Cupboard had been built by DomDaniel himself. It was a place to dump Darke things that were no longer wanted and were impossible to DeActivate. The cupboard snaked deep into the rock and, although it wasn't actually endless, it went on for miles.

Merrin swallowed hard. He knew he had to do it - there was no going back now. Trembling, he muttered the UnBar, grasped the innocent-looking brass cupboard doorknob and pulled. The door opened. Merrin reeled. Ice-cold air laced with the foulest smell - wet dog and rotting meat with a hint of burned rubber - hit him. He retched and spat in disgust.

With a feeling of doom, Merrin peered into the darkness. The cupboard appeared empty, but he knew it wasn't. The Endless Cupboard shifted things about, taking the Darkest deep into the rock. He dreaded to think how far it had taken the bones.

Lifting the candle above his head, Merrin stepped inside. The cupboard snaked deep into the rock like a tendril. As Merrin walked in, the air became cold. After about a dozen steps his candle flame began to gutter in the foul atmosphere, but he pressed on, deeper into the cupboard. Now the flame was growing smaller. It began to glow a dull red, and Merrin became alarmed. If there was not enough air for the flame then surely that meant that there was not enough air for him? Feeling light-headed now, with a high-pitched buzzing in his ears, Merrin took a few more steps and suddenly the candle flame died, leaving for a brief moment the red glow at the end of the wick, and then complete darkness.

Merrin's chest felt tight. He opened his mouth wide to try to breathe more air, but nothing was there.

He knew he had to get out of the cupboard - fast. Gasping, he turned back, only to run straight into an immoveable Thing. In a blind panic, he pushed past the Thing, only to find another in his way, then another. Horrified, Merrin realized that he was trapped - that the long, thin cupboard was stuffed full of Things, and that they were probably still trying to get in, which indeed they were. Outside, an agitated crowd of Things jostled, pushing, scratching and fighting to be the next one inside. A wave of fear engulfed Merrin; then the cupboard floor did something very strange. It rushed up to meet him and hit him on the head.

When Merrin came to he was back in the Observatory, lying on the cold slate floor.

Blearily he looked up, and twenty-six Things stared back. Usually the gaze of twenty-six Things would be enough to send someone into despair forever, but Merrin's eyes would not focus. All he saw was a wavy blur surrounding him, like a large, prickly hedge.

Slowly, Merrin became aware of something on the floor beside him. He turned his head - which hurt - and came face to face with a grubby canvas sack. A garbage sack. Inside, like a litter of kittens, something was moving.

Suddenly wide awake, Merrin leaped to his feet, grabbed the sack and upended it. A tangle of soft, slimy bones slid out across the floor, the small fat bone wearing the ring skittering across the floor with a metallic clink. Merrin stared at it blankly - what was he meant to do now? A bone by his foot twitched. Merrin screamed. Like blind worms, the bones were beginning to move, each one searching for its neighbor - they were ReAssembling.

A bony finger poked his ribs and Merrin screamed. DomDaniel was poking him. He was going to dieeeeeee! The Darke Index was thrust in front of his face and Merrin realized with relief that the bony finger belonged to a Thing. Obediently he read the passage that the Thing's finger was pointing to:

Take the Two-Faced Ring

From the Thumb

Of the One

Who wears It.

Remove the Ring the Other Way:

Your Possession now Holds Sway.

Merrin went over to the small slimy black stick that wore the Two-Faced Ring and looked down at it with revulsion. He steeled himself to pick it up. One, two, three - no, he couldn't do it. Yes, he could - he had to do it. One...two...three - eurgh! He had it. The thumb bone was soft - like gristle. It was revolting. He was going to be sick.

Some seconds later, with a nasty taste in his mouth, Merrin grasped the Two-Faced Ring, knowing he had to pull it over the base of the bone - the Other way. He pulled. It stuck on the wider part of the bone where the joint had been. Merrin fought off panic. It wouldn't come off. Soon DomDaniel would ReAssemble and he'd be cat food. Desperation gave Merrin a kind of courage. He pulled out his pocket knife, put the thumb bone on the floor and sawed the end off the bone. Thick, black liquid oozed from the bone, and the Two-Faced Ring fell free.

Horribly fascinated, Merrin picked up the ring and stared at the broad, twisted band of gold with the opposite facing, evil-looking heads carved in jade. With shaking hands, he consulted The Darke Index:

On your left hand

Upon the thumb

You place the band -

The Two-Faced One.

Trembling, Merrin slid the ring onto his own thumb, pushing away the thought that one day someone might try to take it off his thumb the Other way. At first the ring sat loose on Merrin's thin, grubby thumb with its bitten nail and big knuckle, but not for long. He felt the gold become warmer and warmer until it was almost unpleasantly hot - and then the ring began to tighten. Soon it fit perfectly, but it did not stop there. Getting even hotter, the ring continued to tighten. His thumb began to throb.

Merrin panicked. He leaped up and down, shaking his thumb, yelling and stamping his feet with the pain. Tighter and tighter the ring swelled, turning the end of his thumb first red, then purple and finally a dark, deep blue. At that point, Merrin stopped shouting and stared at it in horror; he just knew that the end of his thumb was about to explode. Would it go pop, he wondered, or would it be a squelchy kind of splat? Merrin didn't want to know. He closed his eyes. And the moment he closed his eyes, the ring loosened its grip, the blood flowed back and Merrin's thumb deflated. The Two-Faced Ring now fit, although it felt tight - just tight enough to remind him of its presence.

Merrin knew that it was his for life - or at least the life of his left thumb.

Merrin was beginning to realize that Darke Magyk was not necessarily on the side of those who practiced it. But he could not stop now. He was trapped, and now he must embark upon the last part of the Enchantment - Darkening the Destiny of AnOther . And that must be done in the Castle, for that was where the Other lived, at the top of the Wizard Tower, as he had once done. Using the same name that Merrin himself once had: Septimus Heap.